Set inlet boundary condition values for turbulence variables based on a diameter  and the reference velocity
 and the reference velocity  for a circular duct flow with smooth wall.  
 More...
 for a circular duct flow with smooth wall.  
 More...
 Collaboration diagram for turbulence_bc_inlet_hyd_diam:
 Collaboration diagram for turbulence_bc_inlet_hyd_diam:| Public Member Functions | |
| subroutine | turbulence_bc_inlet_hyd_diam (face_num, uref2, dh, rho, mu, rcodcl) | 
Set inlet boundary condition values for turbulence variables based on a diameter  and the reference velocity
 and the reference velocity  for a circular duct flow with smooth wall.
 for a circular duct flow with smooth wall. 
We use the laws from Idel'Cik, i.e. the head loss coefficient  is defined by:
 is defined by: 
![\[ |\dfrac{\Delta P}{\Delta x}| = \dfrac{\lambda}{D_H} \frac{1}{2} \rho U_{ref}^2 \]](form_121.png) 
then the relation reads  .
.  depends on the hydraulic Reynolds number
 depends on the hydraulic Reynolds number  and is given by:
 and is given by:
 
 
![\[ \lambda = \dfrac{64}{Re} \]](form_126.png) 
 
 
![\[ \lambda = \dfrac{1}{( 1.8 \log_{10}(Re)-1.64 )^2} \]](form_128.png) 
 , we complete by a straight line
, we complete by a straight line 
![\[ \lambda = 0.021377 + 5.3115. 10^{-6} Re \]](form_130.png) 
From  , we can estimate
, we can estimate  and
 and  from the well known formulae of developped turbulence
 from the well known formulae of developped turbulence
![\[ k = \dfrac{u^{\star 2}}{\sqrt{C_\mu}} \]](form_132.png) 
![\[ \varepsilon = \dfrac{ u^{\star 3}}{(\kappa D_H /10)} \]](form_133.png) 
| [in] | face_num | boundary face number | 
| [in] | uref2 | square of the reference flow velocity | 
| [in] | dh | hydraulic diameter   | 
| [in] | rho | mass density   | 
| [in] | mu | dynamic viscosity   | 
| [out] | rcodcl | boundary condition values | 
| subroutine turbulence_bc_inlet_hyd_diam | ( | integer(c_int), value | face_num, | 
| real(c_double), value | uref2, | ||
| real(c_double), value | dh, | ||
| real(c_double), value | rho, | ||
| real(c_double), value | mu, | ||
| real(kind=c_double), dimension(*) | rcodcl | ||
| ) |